This project should contribute to an improved understanding of relationships between the cellular exudate of inflammation and concommitant tissue destruction and repair by studying the capacity of human monocyte/macrophages to alter the growth of human fibroblasts. Purified human peripheral monocytes are cultured under defined conditions in vitro. The media supporting the monocytes is transferred to fibroblasts in stationary phase (quiescent) and the effects on the number of attached fibroblasts is measured over time. Since the media supporting the monocytes is totally defined, isolation of substances elaborated there by the cells should be facilitated. Such isolations and subsequent characterizations will be carried out.